An NYPD sergeant has been punished for cooking the books in his Queens station house by misclassifying reports and signing other officers’ names to the documents, The Post has learned.

Sgt. Frank Demma of the 102nd Precinct in Richmond Hill – the unit’s burglary sergeant – changed the reports to downgrade break-ins to lesser crimes and other noncriminal activities, his union lawyer said.

The department said Demma was caught changing five reports, and signing other officers’ names an unspecified number of times.

The incidents allegedly occurred last June and were found in a routine audit, an NYPD spokesman said.

Demma pleaded guilty to two counts of “conduct prejudicial to the good order of the department,” according to a police finding made last month and uncovered by The Post yesterday. As punishment, Demma lost 30 days of vacation time.